JP2013151789A - Meter bypass unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a configuration of a meter bypass unit provided with a check valve so as to easily discharge air in a pipe after meter replacement.SOLUTION: A meter bypass unit 1 that has a flow rate selector valve 3 fitted to a base 2 upstream and a partition valve 21 fitted downstream, is fitted with a meter M between the flow rate selector valve 3 and the partition valve 21 detachably using attaching/detaching means 17 and 52, and includes a bypass pipe connecting downstream sides of the flow rate selector valve 3 and the partition valve 21 while bypassing the meter M has a check valve 31 disposed on a primary side of the partition valve 21 and is provided with a drain valve for air vent between a valve seat part of the check valve 31 and a valve body 26 of the partition valve 21. A tip of a plug 71 of the drain valve fixes a reception port.

Description

  The present invention relates to a meter bypass unit for water supply, and more specifically, relates to a meter bypass unit that enables replacement of a water meter or maintenance of equipment such as a check valve to be used with constant water.

Water meters are to be replaced after a certain period. In the case of replacement, the meter that has been used up to now is removed and a new meter is installed, but the water is cut off during the removal and installation, which is inconvenient for the water user. Also, in the case of high-rise apartments, it is necessary to start work after contacting each house that the water is shut off, which requires a lot of labor.

  In order to deal with such a problem, the present applicant has proposed Japanese Patent No. 3042975. In the invention “apparatus for water pipe connection” disclosed in this patent, a three-way valve is used on the upstream side of the meter, cheese is used on the downstream side of the gate valve provided on the downstream side, and the two outlets of the three-way valve are connected. By connecting one of them and one of the two cheese inlets with a bypass pipe that bypasses the meter and switching between these three-way valves and the gate valve, water is normally supplied to the first flow path through the meter. When the meter is exchanged, water is allowed to flow through the second flow path that bypasses the meter so that no water breakage occurs even when the meter is exchanged. In addition, an exhaust drain valve is provided for discharging the air in the first flow path after the meter is replaced. After the meter is replaced, the gate valve is opened and water continues to flow through the second flow path. Flowing water in the opposite direction to discharge the air in the first flow path, then switching the three-way valve to close the second flow path, and water in the normal flow direction to the first flow path I try to make it flow. Thereby, it is prevented that troubles occur in downstream equipment such as a booster pump due to air remaining in the pipe.

Japanese Patent No. 3042974

  By the way, in water supply piping, for example, a check valve may be used to prevent a backflow from the downstream side when the water pressure drops due to some failure on the upstream side. (Meter bypass unit) does not use a check valve to prevent backflow. However, there is a possibility of backflow even in the meter bypass unit, and the effect of attaching a check valve is great. Here, in general, the check valve is attached to the downstream side of the meter, but it is usually provided at the pipe end of the pipe connected to the meter in consideration of workability during maintenance and the like. By the way, when a check valve is attached to the meter bypass unit, the air in the pipe after the meter replacement, which has been conventionally performed, cannot be discharged. That is, even if the gate valve is opened after the meter is exchanged, the check valve is present, so that water cannot flow in the direction opposite to the normal direction as described above.

This invention is made in view of the said problem, and provides the structure which can discharge | emit easily the air in piping after meter replacement | exchange in the meter bypass unit which provided the check valve. In addition, the present invention uses a member that constitutes the above air vent mechanism as a member that fixes the check valve that is detachably attached to the unit, so that the number of parts can be reduced and the check valve can be maintained. A configuration capable of improving the performance is provided.

In order to solve the above-mentioned problems, the present invention is provided with a flow path switching valve connected to the upstream pipe on the upstream side and a partition valve connected to the downstream pipe on the downstream side. A meter bypass unit comprising a bypass pipe that allows the meter to be detachably mounted between the valve and the gate valve, and bypasses the meter to connect the flow path switching valve and the downstream of the gate valve The following configuration was adopted. That is, a check valve is disposed on the primary side of the gate valve, and a drain valve for venting air is provided between the valve seat portion of the check valve and the valve body of the gate valve.
The check valve includes a check valve body attached to the primary side of the gate valve, a receiving port fitted to the check valve body on one end side, and a check valve cartridge removably attached to the receiving port. The check valve main body and the receiving port are engaged with each other by rotating the receiving port with respect to the check valve main body by a predetermined angle after being fitted, and at the position rotated by the predetermined angle, A locking portion for preventing the check valve body from coming off and a locked portion are provided, and the drain valve for air venting is detachable from the drain hole formed in the check valve body and the drain hole. And a drain plug to be inserted, and the tip of the inserted drain plug is engaged with a receiving port that is prevented from coming off to prevent the rotation of the receiving port.
Further, the check valve cartridge can be detachably attached to the receiving port, and can be integrally removed when the receiving port is removed from the check valve body.

  According to the meter bypass unit of the present invention, the check valve can reliably prevent backflow, and the air remaining in the pipe after replacement of the meter or maintenance of the check valve can be reliably discharged. In addition, since the check valve receptacle can be fixed by the drain valve plug for venting air, the number of parts is reduced, and the drain valve is closed and opened by installing and removing the drain plug and fixing the receptacle. Since it can be released at the same time, it has excellent work efficiency. In addition, the check valve cartridge can be integrally removed when the check valve receiving port is removed from the check valve body, and the efficiency of the check valve maintenance work is excellent.

It is front sectional drawing of the meter bypass unit concerning embodiment of this invention. It is the plane sectional view which notched a part. It is a longitudinal cross-sectional view which shows the connection structure by the side of a flow-path switching valve. It is a figure which shows the non-return valve main body of a non-return valve, (A) is front sectional drawing, (B) is plane sectional drawing, (C) is a left view. It is a figure which shows the receiving port of a non-return valve, (A) is front sectional drawing, (B) is plane sectional drawing, (C) is a left view, (D) is a right view. It is an assembly drawing of a check valve.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. 1 and 2 are a front sectional view of a meter bypass unit according to an embodiment of the present invention and a plan view with a part cut away.

  In the figure, a meter bypass unit (hereinafter simply referred to as “bypass unit”) 1 includes a base 3 to which each of the below-described equipment is attached. Moreover, what is shown with the dashed-two dotted line in the figure is the water meter M attached to this bypass unit 1. FIG. Since the configuration in which the equipment connected to the upstream and downstream of the meter using such a base 3 is unitized is also shown in the above-mentioned Japanese Patent No. 3042974, etc., detailed description thereof will be omitted.

  Reference numeral 3 denotes a flow path switching valve attached to the base 2 on the upstream side of the meter M, specifically, a three-way valve, and a switching valve with a built-in ball valve body 4 having a T-shaped internal flow path 4a. A main body 5, primary and secondary ball pressers 6, 7 each having a through-hole communicating with the inside of the valve main body 5, and a bypass side ball press 8 are provided. The flow path switching valve 3 includes one inflow port 9 (connected to the upstream side pipe), and first and second outflow ports 10 and 11. Then, the spindle 12 inserted into the main body 5 is rotated using a handle 13 attached to the head thereof, and the ball valve body 4 is rotated to switch the flow path. Since such a switching valve is known, further detailed description is omitted.

One end of a hollow expansion / contraction pipe 14 is inserted into the secondary ball retainer 7 and is prevented from coming off via a retaining ring 16 by a cap nut 15 that is screwed into the secondary ball retainer 7 (see FIG. 3). . The other end of the telescopic pipe 14 is connected to the meter M by a cap nut 17 that is screwed into a screw formed on the outer periphery of the inlet of the meter M.

As shown in detail in FIG. 3, a screw hole 3 a penetrating inside is formed on the upper side of the switching valve body 3 on the first outlet 10 side, and the plug 18 is detachably screwed into the screw hole 3 a. doing. Reference numeral 19 denotes a seal ring. A shallow outer peripheral groove 7a is formed in the secondary ball retainer 7 at a position corresponding to the screw hole 3a, and two communication holes 7b connected to the groove 7a and the inside are formed in the top and bottom in FIG. Therefore, when the plug 18 is removed, the inside of the secondary side ball retainer 7 is vented to the outside.

A gate valve 21 located downstream of the meter M is attached to the base 2. Inside the gate valve 21, a flow path 21 a penetrating left and right in FIG. 1 is formed. The gate 24 is covered with a lid 23, a spindle 24 is inserted through the lid 23, a valve body 26 is attached to the lower end thereof, and a handle 25 attached to the upper end of the spindle 24 is operated to operate the spindle 24. And the valve body 26 is moved up and down to open and close the flow path 21a.

  Reference numeral 31 is a check valve disposed between the meter M and the gate valve 21. The check valve 31 is generally composed of a check valve main body 32, a receiving port 44 combined therewith, and a check valve cartridge 54 housed therein. The receiving port 44 is connected to the outlet of the meter M by a cap nut 52 on one end side (left side in FIG. 1), the other end is attached to one end side of the check valve body 32, and the other end side of the check valve body 32 is a partition. The valve 21 is connected to the primary side of the flow path 21a. Hereinafter, a description will be given with reference to FIGS.

4A and 4B show the check valve body 32, where FIG. 4A is a front sectional view, FIG. 4B is a plan sectional view, and FIG. 4C is a left side view. The check valve main body 32 is a cylindrical member having a through hole 38. In FIGS. 4 (A) and 4 (B), the large diameter portion 33, the medium diameter portion 34, the small diameter portion 35 and the small diameter portion 35 are arranged in descending order of the inner and outer diameters. A first inclined part 36 and a second inclined part 37 are provided. A protruding portion 39 is formed on the outer peripheral side of the large-diameter portion 33, and a screw hole 40 communicating with the through hole 38 is formed therein. Further, on the inner peripheral side of the large-diameter portion 33, a locking portion 41 of a ridge extending at a predetermined length in the circumferential direction is formed at a position facing each other, and the gap between the end portions of the locking portion 41 is shallow. It is. As described above, the check valve main body 32 is attached with the small diameter portion 35 fitted to the primary side of the flow path 21 a of the gate valve 21.

FIG. 5 shows the receiving port 44, (A) is a front sectional view, (B) is a plan sectional view, (C) is a left side view, and (D) is a right side view. The receiving port is also a cylindrical member having a through-hole 45, and includes a mounting portion 46 having a large inner and outer diameter on the right side as viewed in FIGS. Further, on the end face of the mounting portion 46, a protruding portion 47 to be engaged with the ridge that extends toward the circumferential direction by a predetermined length is formed. The position in the radial direction is substantially the same as the locking portion 41 of the check valve main body 32. Further, the outer peripheral side of the locked portion 47 is a chamfered portion 51 formed at substantially the same angle as the first inclined portion 36 of the check valve main body 32. The length of the locked portion 47 is shorter than the interval between the ends of the locking portion 41 of the check valve main body 32. Further, a shallow recess 48 is formed on the outer peripheral side on the end side of the attachment portion 46. The left side of the sliding part 49 in FIGS. 1A and 1B is a sliding part 49 having a slightly larger outer diameter, and a circumferential groove 50 for receiving the seal ring is formed there. The receiving port 44 is attached to the meter M using a cap nut 52 at the left end thereof, and the left side is inserted and fixed in the hole 38 of the check valve main body 42. This will be described with reference to FIG.

Reference numeral 54 is a known check valve cartridge (hereinafter referred to as “cartridge”). The cartridge 54 includes a central portion opening, and includes a valve seat portion 56, a cylindrical portion 57, a base portion 58, a guide column 59 extending from the base portion 58 toward the valve seat portion 56, a base portion 58, and an end portion of the cylindrical portion 57. The frame body 55 is provided with a plurality of ribs 60 provided at equal intervals in the circumferential direction. As shown in the figure, the cylindrical portion 57 has a plurality of holes 61 spaced apart in the circumferential direction at positions substantially corresponding to the first inclined portion 36 of the check valve main body 32. Reference numeral 62 denotes a valve body, which is guided by a guide column 59 and is always urged toward the valve seat portion 56 by a compression spring 63.

When attaching the check valve 31 to the gate valve 21, first, the check valve body 32 is attached to the gate valve 21 as described above. On the other hand, the cartridge 54 is attached to the receiving port 44. In other words, the valve seat 56 side of the cartridge 54 is inserted into the attachment portion of the receiving port 44 until the end surface of the valve seat portion 56 abuts against the shoulder portion 46 a inside the attachment portion 46. This attachment state can be maintained by the friction of the seal ring 65 disposed between the cartridge 54 and the receiving port 54. In this state, the receiving port 44 is inserted into the through hole 38 of the check valve main body 32 from the base 58 side of the cartridge 54 in a state rotated 90 degrees counterclockwise from the state of FIG. Is pushed until it hits the shoulder 34a of the medium diameter portion 34 of the check valve main body 32. At this time, the chamfered portion 50 of the locked portion 47 of the receiving port 44 substantially contacts the first inclined portion 36 of the check valve main body 32. As described above, since the length of the locked portion 47 of the receiving port 44 is shorter than the distance between the end portions of the locking portion 41 of the check valve main body 32, insertion of the receiving port 44 is not hindered. At this time, the sliding portion 49 of the receiving port 44 fits into the large diameter portion 33 of the check valve main body 32. Reference numeral 53 denotes a seal ring. Further, the rib 60 side portion of the cylindrical portion 57 of the cartridge 54 is fitted into the intermediate diameter portion 34 of the check valve main body 32. The frictional force at this portion is much smaller than the frictional force due to the seal ring 65, and the receiving port 44 is pulled. When pulled out, the cartridge 54 is pulled out together while being held in the receiving port 44.

After inserting the receiving port 44, when the receiving port 44 is rotated by 90 degrees on the opposite side, that is, clockwise, the two locked portions 47 are positioned on the back side of the corresponding locking portions 41, and at that position, the receiving port 44 is located. Is not pulled out from the check valve body 32. At this time, the screw hole 40 of the check valve main body 32 and the recess 48 of the receiving port 44 are aligned in the axial direction and the circumferential direction. When a threaded drain plug 71 is screwed into the screw hole 40 in this state, the tip of the drain plug 71 fits into the recess 48, thereby preventing the receiving port 44 from rotating and being fixed. When the drain plug 71 is removed, the receiving port can be rotated, and the inside of the check valve main body 32 is vented to the outside through the large diameter portion 33 and the first inclined portion 36. Since a hole 61 is formed in the cartridge 54 and an opening is formed between the ribs 60, the flow path 21a between the valve body 62 of the cartridge 54 and the valve body 26 of the gate valve 21 is also vented to the outside. Will be. Reference numeral 72 denotes a seal ring.

Returning to FIGS. 1 and 2, the cheese 81 is attached to the downstream side of the gate valve 21. The cheese 81 communicates with the flow path 21a of the gate valve 21 through a first flow path 82a, a flow path that communicates with the first flow path 82 through a straight flow path, and is connected to the downstream pipe. A second inlet 83 connected to the flow path is provided between the inlet 82 and the outlet 84. The second outlet 11 of the flow path switching valve 3 and the second inlet 83 of the cheese 81 are connected by a bypass pipe 86. Reference numeral 87 is a pilot pipe whose both ends are open at a position on the secondary side of the gate valve 21 and a position near the second outlet of the flow path switching valve 3 of the bypass pipe 86.

  In the bypass unit 1 having the above-described configuration, the flow path switching valve 3 is in a position where the inflow port 6 and the first outflow port 10 communicate with each other, and when the gate valve 21 is open, the first flow from the inflow port 6. The outlet 10, the expansion pipe 14, the meter M, the check valve 31, the gate valve 21, the first inlet 82 and the outlet 84 of the cheese 81 are formed, and the water supply is in a normal use state. In this case, water is supplied through this first flow path. When the meter M is exchanged or the check valve 31 is maintained, the flow path switching valve 3 is switched so that the inlet 6 and the second outlet 11 communicate with each other, and the gate valve 21 is closed. And a second flow path that flows from the inlet 6 of the flow path switching valve 3 to the second outlet 11 and through the bypass pipe 86 to the second inlet 83 and outlet 84 of the cheese 81 is formed. Even at the time of replacement or when the check valve 31 is maintained, water supply to the downstream side is ensured, and these operations can be performed with constant water.

  Next, the procedure in the case of performing meter replacement or check valve maintenance when the above-described bypass unit 1 is used will be described. In the normal water supply state, water is passed through the first flow path passing through the meter M as described above. When the above operation is performed, first, the flow path switching valve 3 is switched so that the inlet 6 and the second outlet 11 are connected, and the gate valve 21 is closed. As a result, the first flow path is closed, the second flow path is opened, and water bypasses the meter M and is sent downstream. Next, the drain plug 71 provided on the gate valve 21 side is opened. As a result, it was sealed between the flow path switching valve 21 and the check valve 31 and between the check valve 31 and the gate valve 21 by switching the flow path switching valve 3 and closing the gate valve 21. The sealing pressure is released. Next, the cap nuts 17 and 52 are loosened and the meter M is removed. At this time, since the sealed pressure is released, the work of loosening the cap nut is facilitated, and the internal water is not ejected during the work. Then install a new meter M. At this time, if necessary, maintenance of the check valve 71 is performed. That is, when the receiving port 33 is rotated 90 degrees counterclockwise, the engaging portion 41 of the check valve main body 32 and the locked portion 47 of the receiving port 44 are disengaged, and the receiving port 33 is pulled from the check valve main body 32. Can be removed. At this time, the cartridge 54 is detached together with the receiving port 33 as described above. After the maintenance is completed, the cartridge 54 is attached to the receiving port 44, and the receiving port 44 is attached to the check valve main body 32. A new meter M is then installed. Even when only the maintenance of the check valve 31 is performed without exchanging the meter, the operation is performed in the same procedure as described above.

  When the installation of the new meter M is completed, a position for flowing the flow path switching valve 21 through the first flow path (a position for connecting the inlet 6 and the first outlet 10) and a position for flowing through the second flow path (flow) The position is switched to an intermediate position between the inlet 6 and the second outlet 11. That is, the water flows in both the first flow path and the second flow path. Since air has entered the first flow path (between the flow path switching valve 3 and the gate valve 21) after the meter replacement, the second flow path that passes through the bypass pipe in this state is used. While maintaining water flow downstream, the air that has entered the first flow path is discharged from the screw hole 40 that is an air vent hole. When water overflows from the screw hole 40, the air venting is completed, and the plug 71 is screwed and sealed, and the receiving port 44 is fixed. Then, the gate valve 21 is opened, and the flow path switching valve is completely switched to the first flow path. As a result, the first flow path is opened and the second flow path, that is, the bypass flow path is closed.

In the bypass unit configured as described above, a member on the flow path switching valve side of the bypass unit that does not include a conventional check valve can be used in common. Alternatively, when a bypass unit that does not include a conventional check valve is changed to a unit with a check valve, the member on the flow path switching valve side can be used as it is. In that case, the drain plug 18 is opened before the drain plug 71 on the gate valve side is opened in the previous meter replacement procedure, thereby releasing the water pressure sealed between the switching valve and the check valve. May be. And after switching a flow-path switching valve to the intermediate position for venting, this plug is closed. Thereby, air can be surely vented by discharging air from the end of the pipe part to be ventilated (the end opposite to the side into which water flows). If maintenance of the check valve is not required at that time, the drain plug 71 on the gate valve side is not opened continuously to the drain plug 18 on the channel switching valve side, but after the meter replacement, The plug 18 may be opened after being closed. The meter replacement operation is facilitated because the sealed pressure between the flow path switching valve and the check valve may be released. And after closing the plug 18, the plug 71 by the side of a gate valve is opened, and air is vented from here.
The pilot pipe 87 is provided to prevent water from staying in the bypass pipe 80 during normal use, that is, when water is supplied through the first flow path. That is, a part of the water that flows in the forward direction is sent to the upstream end in the bypass pipe 80 and flows to the outlet 84 to prevent water from staying in the bypass pipe.

Claims (3)

  Attach a flow path switching valve connected to the upstream pipe on the upstream side, and a partition valve connected to the downstream pipe on the downstream side, and use attachment / detachment means between the flow path switching valve and the partition valve. In a meter bypass unit including a bypass pipe that connects the flow path switching valve and the downstream side of the gate valve by bypassing the meter, the meter can be detachably attached to the primary side of the gate valve, A meter bypass unit comprising a check valve and a drain valve for venting air between a valve seat portion of the check valve and a valve body of the gate valve. 2. The meter bypass unit according to claim 1, wherein the check valve is a check valve body that is attached to a primary side of the gate valve, a receiving port that is fitted to the check valve body at one end, and is removable to the receiving port. A check valve cartridge attached to the check valve body, and the check valve body and the receiving port are locked to each other by rotating the receiving port with respect to the check valve body by a predetermined angle after being fitted. A locking portion for locking the receiving port from the check valve body and a locked portion at a position in the rotational direction, and the air vent drain valve is formed on the check valve body. A drain plug that is removably inserted into the drain hole, and the tip of the drain plug that is inserted engages with a retaining port that is prevented from coming off to prevent rotation of the receiving port. Meter bypass unit. 3. The meter bypass unit according to claim 2, wherein the check valve unit is detachably attached to the receiving port, and is configured to be integrally removed when the receiving port is removed from the check valve body. A featured meter bypass unit.

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